Field
Embodiments of the invention relate generally to the recovery of liquid hydrocarbons from subterranean reservoirs, and more particularly to methods and systems to calculate and optimize reservoir wettability for economic estimation and enhancement of liquid hydrocarbon production.
Background Information
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Liquid hydrocarbons, which the purposes of this patent application, includes oil, condensate, tars, and other liquid hydrocarbons, as well as entrained gaseous hydrocarbons, are contained in, and recovered from, reservoirs and underground formations. To access these liquid hydrocarbons, wells are typically drilled from the surface down into the subterranean formations, and the liquid hydrocarbons are recovered through the wells.
Initially, the liquid hydrocarbons may be recovered through primary extraction. Primary extraction may use natural reservoir pressure to force the liquid hydrocarbons into the well. However, typically not all of the liquid hydrocarbons may be recovered through primary extraction. At some point, the reservoir pressure may decline so far that residual liquid hydrocarbons may be held too tightly within the subterranean formation (e.g., due to adhesive interactions between the oil and the rock) and may be economically unrecoverable through primary extraction. Historically, the amount of remaining liquid hydrocarbons may be significant, over half of the original oil or other liquid hydrocarbons. In shales or tight sands that are hydrofracked the amount of liquid hydrocarbons remaining after primary extraction often exceeds 90%.
Secondary extraction is commonly used in order to recover some of the remaining liquid hydrocarbons. A common form of secondary extraction involves injecting a medium known as an injectate, such as water (e.g., seawater or terrestrial water), into the subterranean reservoir in order to mobilize and recover additional liquid hydrocarbons.